The present invention relates to glove liners designed for protection from chemical toxic agents utilizing combination of liner materials to improve moisture management, hand dexterity and functional fit.
Chemical protective gloves are required for protection from toxic agents in liquid and vapour forms. Depending on specific threat environments, gloves can be worn for extended periods of time anywhere between 24-48 hours. Gloves that are impermeable to chemical agents and water vapour may cause considerable discomfort and loss of manual dexterity. Reductions in manual dexterity can result from numbness, tingling, stiffening or swelling in the fingers and knuckles. The skin of the hands may become saturated with moisture causing the outer layer of the skin to swell and soften. In severe cases permanent damage to the hands can result due to maceration of the skin.
Commercially available glove liners used in chemical protective glove are typically string knit using knitting machines with various knitting gauge options, for different yarn sizes. Liners were available in cotton, nylon, polyester or wool. Sewn liners such as nylon inspector""s gloves or cotton photographer""s gloves are also available and are constructed using conventional sewing techniques. The sewn gloves inspected were only available in limited number of smaller sizes and were poorly constructed. A significant problem with sewn gloves is the increase in bulk around the fingers and hands caused by excess seam allowances. Commercial gloves were available only in a limited selection of fiber content that were not very effective with respect to moisture absorbency. The design of the glove liners was also bulky and poor fitting that would eventually cause hand malaise and degradation in hand dexterity if worn with a polymer protective glove.
While there have been discoveries on improved materials and methods of manufacturing glove and glove liners (see, for example, U.S. Pat. Nos. 4,947,486, 5,123,119 and 5,568,656), there has been no comprehensive study being conducted on suitable materials for glove liners for use in chemical protective gloves. Accordingly, there remains a need for better materials and means of manufacturing glove liners for this type of specialized gloves.
In an earlier study, the inventor of the present invention evaluated various types of glove liner materials (see Trembaly-Lutter, J. F., Lang, J. Q., Pichette, D AEvaluation of Candidate Glove Liners for Reduction pf Skin Maceration in Chemical Protective Gloves @Performance of Protective Clothing: Fifth Volume, ASTM STP1237, James S. Johnson and S. Z. Mansdorf, Eds., American Society for Testing and Materials, 1996. Pp 296-310). It was found that viscose fibers offered the absorbency properties and polymester fibers demonstrated faster dying times. While incorporating LYCRA (trademark) yarns into the glove design did not change the absorbency properties, and yet it reduced the drying time and improved the functional fit of the glove.
In view of this general knowledge, it is highly desirable to examine the various effects of yarn density, yarn count and fabric structure of these materials in order to come up with the best liners for chemical protective gloves.
The present inventor examined more than seventy types of glove liners with a view to develop the best material specification to be used in chemical protective gloves. Using a specific fiber content, yarn tex and fiber structure, the glove liner according to the present invention is able to manage sweat accumulation inside impermeable gloves while minimizing interference with manual dexterity.
An object of the present invention is to develop a new glove liner which absorbs sweat and keeps the hand dry. Another object of the present invention is to provide a liner which is thin enough not to interfere with hand manipulation. A further object of the present invention is to produce a glove liner that offers functional fit to a wide population of users.
These and other objects, advantages and features of the invention shall be described below.